Hi i have a very small red lump on my penile shaft anything to be worried about it sometimes disappears when i wash well what could it be thanks .

Hemangioma?: A "red lump" on the skin (penis or anywhere) that vanishes and reappears pretty much has to be related to blood vessels, e.g. a hemangioma (blood vessel "mole") or telangectasia (a small tangle of blood vesels), etc. These could be more prominent with increased blood flow, e.g. during erection, warm water, etc. No STD would do this; e.g. I doubt a genital wart. But show a doc you remain concerned.